1. Field of the Invention
The present invention relates to a communication system, and more particularly, to a communication system for canceling channel interference and a method thereof.
2. Description of the Prior Art
A full duplex Ethernet communication is accomplished by four unshielded twisted pairs, as shown in FIG. 1. In FIG. 1, signal interference existing in the Ethernet is shown; for example, the transmitted signal of the transmitter 110a forms an Echo in the receiver 120a, and the transmitted signals of the transmitters 110b, 110c and 110d form near-end cross talk (NEXT) in the receiver 120a. 
For canceling the interference signals mentioned above, an interference canceling module, such as a filter, is utilized to process the received signal in the time domain. The filter generates an interference cancellation signal approximate to the interference signal respectively according to the transmitted signals of the transmitters 110a, 110b, 110c and 110d and the estimated channel impulse response. Then, the signal that should be received by the receiver 120a is found after the interference cancellation signal is subtracted from the received signal. However, the characteristics of the Echo and NEXT are not the same: the required taps of the filters utilized to simulate the Echo and NEXT are different. For example, under 10G Ethernet system, filters having about 250-500 taps and 800-1000 taps are required to simulate the NEXT and Echo respectively. The circuit complexity and the power consumption are both significant.